[Middle English, from Latin Trōiānus, from Trōia, Troy, from Greek, from Trōs, the mythical founder of Troy.] Tro'jan adj.
Tro·jan 2 (trō'jən) adj. Of or relating to a celestial body, especially an asteroid, that is in one of the Lagrangian points of a two-body system. Used especially of any of a group of asteroids that orbit at Jupiter's distance from the sun, but 60° ahead of or behind the planet.
[From the names of heroes of the Trojan War used for these asteroids.]